The historian Frederick J. Turner wrote in the 1890's
that the agrarian discontent that had been developing
steadily in the United States since about 1870 had been
precipitated by the closing of the internal frontier--that is,
the depletion of available new land needed for further
expansion of the American farming system. Actually,
however, new lands were taken up for farming in the
United States throughout and beyond the nineteenth
century. The emphasis of the presumed disappearance of
the American frontier obscured the great importance of
changes in the conditions and consequences of
international trade that occurred during the second half of
the nineteenth century. Huge tracts of land were being
settled and farmed in Argentina, Australia, Canada, and in
the American West, and these areas were joined with one
another and with the countries of Europe into an
interdependent market system. Consequently, agrarian
depressions no longer were local or national in scope, and
they struck several nations whose internal frontiers had
not vanished or were not about to vanish. Between the
early 1870's and the 1890's, the mounting agrarian
discontent in America paralleled the almost uninterrupted
decline in the prices of American agricultural products on
foreign markets.